Source: wikibot/hopf-conjecture

= Hopf conjecture
{wiki=Hopf_conjecture}

The Hopf conjecture is a statement in differential geometry and topology that concerns the curvature of Riemannian manifolds. More specifically, it was proposed by Heinz Hopf in 1938. The conjecture states that if a manifold is a compact, oriented, and simply connected Riemannian manifold of even dimension, then its total scalar curvature is non-negative.